HPA: Improve pod selection accuracy across workload types

[omerap12]

Enhancement Description

HPA may include metrics from unrelated pods if they share the same labels as the target workload. This can cause incorrect scaling, such as staying at maxReplicas even when real usage is low. This proposal updates the HPA to only use pods directly managed by the target workload, avoiding incorrect metrics and improving scaling accuracy.

• One-line enhancement description (can be used as a release note): Improve HPA pod selection accuracy across workload types
• Kubernetes Enhancement Proposal: [in progress]
• Discussion Link:
  • 20 May 2025 SIG Autoscaling meeting
  • HPA stuck at maxReplicas even though metric under target kubernetes#120875 (comment)
• Primary contact (assignee): @omerap12, @adrianmoisey
• Responsible SIGs: SIG Autoscaling
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): 1.34
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update PR(s):

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

[omerap12]

/sig autoscaling